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There is an excellent article on the efficiency of transportation systems:
Gleave, J. (2019) Space/Time and Transport Planning, Transport Futures, https://transportfutures.co/space-time-and-transport-planning-1aae891194e5 [Last accessed: February 25, 2019].
It is highly recommended not just for academics (including students) but also for anyone interested in transportation and traffic. It’s like a crash course in transportation engineering with a lot of basic concepts in traffic engineering and traffic flow theory being presented for easy understanding by anyone. Enjoy!
We start the month of March with a compilation of photos of vertical curves (mostly sags). These were taken along the Andaya Highway, which serves as the main bypass road in Camarines that allows travellers to bypass, for example, Daet.
These photos do not have captions and I leave it to my readers to have an appreciation of the features of these sections. These include wide carriageways with paved shoulders. There are also sections that have no shoulders. For most photos, the pavement appears to be in good condition. However, the same cannot be said for much of the highway, sections of which are being rehabilitated along with several bridges.
I recently featured photos of the old zigzag road along the Pan Philippine Highway that is more popularly known as the “Bitukang Manok”. Those photos were taken on an early morning while we were on our way to Bicol earlier this month. Following are photos of the old zigzag road taken on the afternoon of our return trip to Manila.
Crossroads – at the intersection at the southern end where travellers decide whether to take the Bitukang Manok or the newer and easier bypass road
The sign states: Vehicles with 6 or more wheels are prohibited from using the old zig-zag road.
Sign for the Quezon National Forest Park – this designation is attributed to a former President and local congressman
Here’s a photo of one of the more challenging sections. A team of flagmen manage traffic by giving turns to either direction, ensuring slower speeds and wider turning at the hairpin curve. Travelers often toss coins as a token of gratitude for these flagmen who man this challenging section of the national highway 24 hours/day.
The barriers and signs along Bitukang Manok have been upgraded and are well-maintained.
Approach to the northern end of the old zigzag road
Directional sign at the other end of Bitukang Manok showing the options for travellers and another advisory stating the prohibition of large vehicles along the old zigzag road.
I woke up from a long nap just before we entered a major zigzag section of the Pan Philippine Highway that is more popularly known as the “Bitukang Manok”. That literally translates to “chicken innards or intestines”, which is how many travellers would describe the alignment of this section of the national highway network. We decided to take the “old zigzag road” instead of the “new diversion road” since the latter is known to be already congested especially as trucks and buses take this road instead of the zigzag.
Expectedly, the road offered all kinds of curves and grades throughout. I was glad to see relatively new barriers already installed or constructed along the entire length of Bitukang Manok.
Here is a particularly challenging section combining sharp hairpin curves with steep inclines.
We caught up with this rider along a relatively straight and level segment of the road
There are flagmen strategically deployed along the most difficult parts of the road including this one that might lead inexperienced or erring drivers to drive/ride straight off a cliff.
Here’s another hairpin curve; this time on the way down from the mountain.
The final turn of the road before it merged with the diversion road
Sign at the other end of the road showing travellers the divergence of the national highway into the “old zigzag road” and the “new diversion road”. Notice the platoon of southbound trucks at right.
I remember Bitukang Manok as a dreaded section among travellers before not just from the safety viewpoint but also because many can get sick (e.g., motion sickness that may result into throwing up) going through the section especially if the driver is not as smooth in manoeuvring the vehicle through the zigzags. There were also long distance bicycle races before where the Bitukang Manok featured as the main challenge to the best cyclists and the winner of that leg of the race was pronounced as “king of the mountain”.
A friend recently posted an episode on his vlog that featured the excessive signage we now find along many roads. I thought this was a relevant topic as, for one, there are many signs that are basically contributing to the “visual pollution” that tend to either distract travellers or make them numb about these signs. Hindi pa kasali dito ang mga LED/video ads that are now installed around the metropolis. Being a distraction means they may lead to road crashes. But then there is also the issue of clutter and obstruction. I noticed that many signs have been installed without consideration of the spaces required by pedestrians and cyclists. Many seem to have been forcibly installed at locations blocking the path of pedestrians.
So which among these signs is the only one that should be there? Only one and that is the one in the middle informing travellers of the signalised intersection ahead. The others are basically ads masquerading as signs (directional signs to be more specific).
I avoid describing inappropriate signs as ‘illegal’ simply because the proponents were given permission for installation by local government units including the MMDA. LGUs seem to benefit from these as I also see inappropriate signs bearing the logos or slogans of LGUs. Meanwhile, the DPWH seems to be mum about this concern, which appears to be a non-issue among the government entities involved. What do you think about such ads pretending to be road signs?
Here is another good read especially for those who advocate or even just beginning to appreciate the concept of people-oriented transportation:
VannPashak, J. (2018) “Design for humans as they are, not as you want them to be,” http://www.medium.com, https://medium.com/@jvannpashak/design-for-humans-as-they-are-not-as-you-want-them-to-be-ef95076c0988 [Last accessed: 11/23/2018].
In a recent symposium where I made a presentation about low carbon transport and visioning and re-imagining transport, I was asked how we can re-design our transportation to be more people-oriented than car-oriented. I replied that we have to do a lot of unlearning. That is, many planners and engineers would need to unlearn many things they’ve learned in school and those they got from their workplace. One convenient excuse for not coming up with a better design, for example, is that certain planners or engineers just followed what their offices or agencies have been doing. What if what their offices and agencies (and consequently their seniors at work) where wrong all these years and what was “ginagawa na” or “nakasanayan” have led to deficient outcomes? I even joked about whether these offices or agencies were “open minded” referring to a favourite by-line by networking companies. Being open-minded in the context of having people-oriented transport solutions would be difficult if everything was “nakakahon” because these were what you learned from school and/or the workplace. It is difficult to admit that something was and is wrong.
The recent news about the groundbreaking for the C-6 expressway led some people to this site and looking for information on C-6. Here are more photos I took last month (January 2018):
The future northbound lanes of C-6 is currently under rehabilitation and are being upgraded to Portland cement Concrete Pavement (PCCP). The new southbound lanes currently serve the two-way traffic.
The sign is an old one and perhaps still in use as a barrier more than for information
You see a lot of people jogging, walking and cycling along the finished road. It shows the demand for spaces for such activities, including recreation, and a similar situation may be observed along C5 before and along the perimeter of Libingan ng mga Bayani where a lot of people do exercises and other activities along road sections that are closed to vehicular traffic.
With one lane completed the second lane is prepared for pouring of concrete. You can see the formworks along the median.
Other sections have yet to be prepared for concreting but have been stripped of the old pavement (Asphalt Concrete pavement or ACP).
What you see here at right is the compacted base/sub-base layer. The forms have not been installed yet.
Backhoe and roller at the worksite.
A grader in action.
I will post more photos later from the next time I pass by the area. From what I’ve hear so far, traffic has eased along the expanded Barkadahan Bridge but there are still bottlenecks to address along this alternative route. There will also be a need to have a higher capacity, less friction connection between C-6 and C-5 as traffic along C-6 increases and it’s become quite obvious that Taguig’s narrow streets cannot handle this increasing travel demand between the two highways. It makes sense to have a higher quality, limited access road for this purpose since Taguig roads are already congested and through traffic poses a safety hazard to the residential areas where vehicles travel through.